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How do I turn off laptop screen when external monitor is connected? Turning brighness down to zero is not any good as windows will keep popping up on external screen.

Closing the lid and hoping it will figure out what I want sometimes works but very unreliably. Is there any reliable simple way to do it?

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Kyle's solution is usually reliable and definitely answers your question. You might need to wait until the machine is completely in sleep mode, you can see this by observing the pulsating light. If it doesn't work for you, that's another issue altogether. – Daniel Beck Jan 26 '11 at 8:43
check this out:… – user1015230 Dec 25 '11 at 23:25

Yes, there is a way to do it. With the laptop on and open, attach the external power and monitor. If you're planning on using a Bluetooth keyboard or mouse, go into the Bluetooth preferences under "Advanced..." and check the box allowing Bluetooth devices to wake the computer and connect the Bluetooth devices.

Next, close the lid. This will put the computer to sleep. Once the computer is sleeping (the light pulsates, the fan stops) press a key on the Bluetooth keyboard or plug in a USB keyboard/mouse. This will wake the computer with the lid closed. After a few seconds it will figure out that the only screen it can use is the external screen, and you'll be good to go.

If you want to use the keyboard and trackpad of your MacBook instead of using an external keyboard/mouse, follow the steps above but instead of plugging in the USB keyboard/mouse, just plug any USB item in (iPhone, thumbdrive, etc). This will still wake the computer. Once it's woken up you can open the lid and use the keyboard and trackpad and the MacBook screen will still remain off.

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I obviously have USB keyboard/mouse and I've never used Bluetooth. What you say (making computer sleep, trying to wake it up with lid closed) sometimes work - highly unreliably. Sometimes Macbook realizes it has external monitor, sometimes it just goes back to sleep right away. – taw Mar 5 '10 at 7:35
@t-a-w Do you have it plugged in at all times? IIRC it won't work if you don't have it on external power. Apart from that I don't know what it could be except possibly a defective unit as I've had no problems with my method above. (mid-2007 MacBook) – Kyle Cronin Mar 5 '10 at 7:51
Power/USB keyboard/USB mouse are plugged all time. But Surely there must be a way to programmatically tell macbook about it all, right? – taw Mar 6 '10 at 6:35

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